The present invention relates to portable containers and more particularly to a container with a refillable liquid core.
Insulated coolers are known in the art. These coolers typically have spaced inner and outer walls made of a high strength plastic or metal and include a removable cover. The space between the walls is typically filled with an insulating material such as polystyrene. A drawback to this type of cooler is that a user must insert ice or a cold pack in the container to keep items cold. The ice and cold packs take up valuable volume within the container and the melted water from the ice can damage items in the container.
Insulated drinking cups are known in the art. These cups typically hold 8-32 oz of liquid and have a handle for grasping. These cups have spaced inner and outer walls. The space between the walls may be filled with an insulating material or a liquid. The liquid is installed by the manufacture and sealed to prevent spillage. The user cannot change the quantity of liquid. The entire volume between the inner and outer walls may not be completely occupied by the liquid so as to allow for a change in volume of the liquid as its temperature changes. A drawback to this type of cup is that the liquid cannot be removed and hence the weight of the cup cannot be lessened to make it easier for a user to transport or a manufacture to ship. This becomes more important as the size of the drinking cup increases. Another drawback is that these cups do not have a cover that would prevent heat loss. A sealed core may also present a problem if the user wishes to heat the liquid in a microwave or similar oven.
What is needed is a container having a space between an inner and outer core that can be filled with a removable thermal mass, preferably a readily available liquid such as water.
The invention is directed to a portable container for keeping items cold or hot. In one embodiment the invention provides a container having an inner and outer core with a space between that can be filled with a liquid. The liquid may chilled or frozen or alternatively heated prior to use. The container also having a user removable seal to allow for removal of the liquid to reduce the container weight when not in use. The cooled liquid thereafter helping to keep items in the container cool and the heated liquid helping to keep items in the container warm for an extended period of time.